The Republic of Lucca was a minor state in the Tuscan region, whose main distinction is remaining an independent Republic for most of its history. As with Florence and Siena, Lucca emerged out of the collapse of the Medieval Tuscan Principality and prospered under republican rule. Its main achievement, surviving, was due to a combination of astute economics and politics. Alliances with Milan and the Holy Roman Empire ensured it continued to exist as a bulwark against the expansionist Florentine state. Economically, it sought to secure the valuable Serchio Valley, which guaranteed a source of wealth for the small state in the form of salt and other raw minerals.

The region on this map shows a simplified view of the Luccan State as it was at the time of Italian unification in 1871. The modern-day administrative borders of Lucca also mostly correspond to this depiction. The Serchio Valley was never entirely under Luccan control, and the rival powers of Moderna, Florence, and Genoa at various times seized portions of the valley. Likewise, at its height in the 15th century, Lucca also controlled much more territory to the East, exercising some dominion over the city of Pistoia. However, Lucca lost most of this territory in subsequent wars to Florence.